Knife edge endless loop book cutter

ABSTRACT

A band type of knife has a bevelled edge for cutting unbound sheets of a book held on a conveyor. The saw band is held by guides in the path of the book with the bevel at right angles to the face of the book sheets and with the band inclined relative to the sheets at an angle convergent in the direction of band travel so that the band saw pulls away from the uncut portion of the sheets.

United States Patent Aspinwall et a1.

KNIFE EDGE ENDLESS LOOP BOOK CUTTER Inventors: Peter Aspinwall, Wheaten,111.;

Richard H. Barbour, ,Ir., Milton, Mass.

Assignee: Comstock & Wescott, lnc.,

Cambridge, Mass,

Filed: Jan. 23, 1974 Appl. No.: 435,707

U.S. Cl. 83/174; 83/4091, 83/4352;

83/788; 83/809; 83/820 Int. Cl. B26d 1/46 Field of Search 83/174, 788,809-813,

References Cited UNITED STATES PATENTS Heldmann 83/820 X June 17, 19751,248,253 11/1917 Bredenberg 83/409 X 1,551,167 8/1925 Orlow 1. 83/1741,635,165 7/1927 Adamsky 83/409 X 2,524,016 9/1950 Hall 83/174 X2,670,768 3/1954 Yohn 83/820 X Primary Examiner-J. M. Meister Attorney,Agent, or Firm-James H. Grover [57] ABSTRACT A band type of knife has abevelled edge for cutting unbound sheets of a book held on a conveyor.The saw band is held by guides in the path of the book with the bevel atright angles to the face of the book sheets and with the band inclinedrelative to the sheets at an angle convergent in the direction of bandtravel so that the band saw pulls away from the uncut portion of thesheets.

7 Claims, 3 Drawing Figures SHEET PATENTEDJUN17 1975 CLEANING STATION IKNIFE EDGE ENDLESS LOOP BOOK CUTTER BACKGROUND OF THE INVENTION Knifeedge band saws have been used for cutting various sheet materials suchas leather, but as hitherto available such knife edge band saws have notbeen used for cutting paper, particularly paper in the form of thesheets of a book.

Accordingly the object of the present invention is to provide book orother paper sheet cutting apparatus with a band knife which will make aclean cut through the sheets with very little force applied to feed thesheets, and which cuts off highly salvagable scrap with little damage tothe scrap.

STATEMENT OF INVENTION According to the invention book cutting apparatuscomprises a travelling knife edge cutter including an endless loopcarrying a cutting edge and means to guide the loop through a straightportion at cutting station; a book conveyor for moving a book throughthe cutting station, and means on the conveyor for holding the book withthe face of the book sheets facing substantially parallel to the cuttingedge; the cutting edge having a bevel angle and the loop guide meansholding the cutting edge inclined to the face of the sheets laterally ofloop travel substantially at the bevel angle and with the bevel normalto the sheet face.

Preferably, in addition to the bevel inclination, there is a secondinclination between the blade and sheet face at an angle convergent inthe direction of cutter travel so that the cutting edge pulls on thepaper in a direction away from the uncut portion of the sheets.

DRAWINGS FIG. I is an isometric view of a band saw book cut tingapparatus according to the invention;

FIG. 2 is a fragmentary plan view of the apparatus of FIG. 1; and

FIG. 3 is an enlarged side view of a portion of the apparatus.

DESCRIPTION Shown in FIG. 1 is a band knife type of book cuttingapparatus comprising a table 1 on which is mounted a band knifecomprising an endless, knife edge, band 2 supported on idler rolls 3 anda drive roll 4 connected to a drive motor 6, and driven by the motor inthe direction indicated by the arrow 2*. As explained more fullyhereinafter, the endless band 2 has a cutting edge 7 with two bevelangles 70 and 7b which in their travel are continuously honed byabrasive wheels 8 driven by motors 9. After being sharpened by theabrasive wheels 8 the band 2 passes a cleaning station 11 which removesabrasive and book cutting byproducts from the cutting edge 7. The band 2then extends on a straight portion through a book cutting station 12.

A chain conveyor 13 carries a series of book holders l4, of which one isshown, through the cutting station. The book holder comprises a base 16with a fixed rear wall 17. One or more books B are pressed forwardly bythe wall 17, with the portion of the book to be trimmed off extendingbeyond a trim line 21. Each book B comprises a number of collated sheets5, the outer sheets of the book comprising a face F. The chain 13conveys the book holder in the direction indicated by the arrow 14*.

As shown in FIGS. 1, 2 and 3, the straight portion of the bank passesbetween guide plates 23a and 23b mounted on a standard 24 extendingupwardly from the table I. A back up plate 26 is slidingly held in theguide way between the guide plates and abutting the rear edge of theband. A screw 27 driven by a hand wheel 28 and threaded in a block 29adjustably urges the sliding plate 26 against the rear edge of the band2 so as to hold the cutting edge of the band beyond the guide plates 22and 23.

According to one aspect of the invention the guide plates 23a and 23bare inclined to the face F of the leading book B such that the plane ofthe bevelled edge 7a is perpendicular (normal) to the sheet face F.(FIG. 2) Typically the bevel angle AI is 7 to l0 Preferably the taperedforward end 30a of the guide plate 23 a is tapered parallel to the bevel7a with a slight clearance 31 inwardly of the plane of the bevel edge70. The other plate 23b has a similar taper 30b. Also preferably theplate is very slightly inclined (e.g. 1) away from the trim line 21.These arrangements allow the bevel angle 7a of the cutting edge to beheld very precisely by the guide plates 23a and 23b at the normal angleto the face F of the sheets S to be cut insuring a clean cut. Assuccessive scrap strips are cut from the sheets outside the trim line 21they pass the tapered end 3012 of the guide plate 23b with minimuminterference, and the cut book edge on the trim line clears the taper30a of the guide plate 230.

In another aspect of the invention shown most clearly in FIG. 3 the bookholder I4 is inclined on the chain 13 at an angle selected by a wedge 15under its base 16. Consequently the forward face F of the clamped booksB is inclined such that the vertical angle A2 included between thecutting edge 7 (which in this case is parallel to the direction 2* ofband movement) of the band 2 first enters the face F of the book at thebook edge F*. That is the angle between the direction of band movement2* and sheet face F is convergent in the upward direction of bandmovement. Although this angle A2 is somewhat exaggerated in FIG. 3 itmay be a few degrees, for example, 1 or 2.

With the knife edge cutter at a blade speed of 2,500 feet per minute,for example, rapid, high quality trimming of telephone books,dictionaries and other very thick books can be achieved with a very lowdrive force in the order of lO to 20 lbs. Such a drive force permits theuse of gravity feed. Very clean, unwrinkled and untorn scrap is trimmedfrom the book without frictional engagement or jamming of the plate inthe kerf at the trim line. Power consumption in driving the cutting bandis substantially below that required for prior forms of trimmingcutters. The band is not only substantially less expensive (e.g. 50percent) but also, by virtue of its being continuously sharpened, can beused for as long as one month without being removed for honing orreplacement. In contrast a guillotine knife in the same service must beremoved and sharpened approximately once a week. In addition to theabove advantages, the trim of the book is accomplished with a very highquality out.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

We claim:

1. Apparatus for cutting the sheets of a book comprising:

a travelling knife edge cutter including an endless loop carrying acutting edge and means to guide the loop through a straight portion at acutting station;

a book conveyor for moving a book through the cut ting station. and

means on the conveyor for holding the book with the face of the booksheets facing substantially parallel to the cutting edge.

the cutting edge having a bevel angle and the loop guide means holdingthe cutting edge inclined to the face of the sheets laterally of looptravel substantially at the bevel angle and with the bevel normal to thesheet face. and

the book holding means and cutter loop guide means holding the sheetface at an angle to the straight portion convergent in the direction ofcutter travel with the plane of the sheet inclined forwardly in thedirection of book movement so that the cutting edge pulls on the sheetsaway from the uncut portion of the sheets.

2. Apparatus according to claim 1 wherein the convergent angle is l to afew degrees.

3. Apparatus according to claim 1 including cutting edge sharpeningmeans disposed in contact with the bevel for continuous sharpening ofthe edge. and wherein the loop guide means includes a back up for theloop adjustable to advance the blade outwardly of the guide means aftersharpening while maintaining the normal inclination of the bevelrelative to the sheet face.

4. Apparatus according to claim 1 wherein the cutting edge has a secondbevel angle on the opposite side of the loop from the first said bevelangle.

5. Apparatus according to claim 4 wherein the loop guide means includestwo opposed plates forming a guideway for the straight portion of theloop therebetween, one of the plates abutting the loop on the side ofthe first bevel angle and having a tapered face substantially parallelto the first bevel angle.

6. Apparatus according to claim 5 wherein the tapered face is slightlydisplaced from the plane of the first bevel angle toward the loop.

7. Apparatus according to claim 5 wherein the other guide plate has atapered face substantially parallel to the second bevel angle.

1. Apparatus for cutting the sheets of a book comprising: a travellingknife edge cutter including an endless loop carrying a cutting edge andmeans to guide the loop through a straight portion at a cutting station;a book conveyor for moving a book throuGh the cutting station, and meanson the conveyor for holding the book with the face of the book sheetsfacing substantially parallel to the cutting edge, the cutting edgehaving a bevel angle and the loop guide means holding the cutting edgeinclined to the face of the sheets laterally of loop travelsubstantially at the bevel angle and with the bevel normal to the sheetface, and the book holding means and cutter loop guide means holding thesheet face at an angle to the straight portion convergent in thedirection of cutter travel with the plane of the sheet inclinedforwardly in the direction of book movement so that the cutting edgepulls on the sheets away from the uncut portion of the sheets. 2.Apparatus according to claim 1 wherein the convergent angle is 1* to afew degrees.
 3. Apparatus according to claim 1 including cutting edgesharpening means disposed in contact with the bevel for continuoussharpening of the edge, and wherein the loop guide means includes a backup for the loop adjustable to advance the blade outwardly of the guidemeans after sharpening while maintaining the normal inclination of thebevel relative to the sheet face.
 4. Apparatus according to claim 1wherein the cutting edge has a second bevel angle on the opposite sideof the loop from the first said bevel angle.
 5. Apparatus according toclaim 4 wherein the loop guide means includes two opposed plates forminga guideway for the straight portion of the loop therebetween, one of theplates abutting the loop on the side of the first bevel angle and havinga tapered face substantially parallel to the first bevel angle. 6.Apparatus according to claim 5 wherein the tapered face is slightlydisplaced from the plane of the first bevel angle toward the loop. 7.Apparatus according to claim 5 wherein the other guide plate has atapered face substantially parallel to the second bevel angle.